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You searched for: subject:"PERIODIC VARIATIONS"
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[texts]FORTRAN program for calculating the trajectory of projectiles - Gylden, N.
A FORTRAN program is described for numerical calculation of projectiles' trajectories with two degrees of aeromechanical freedom. Dupuis' law of air resistance is applied under OB expansion unknown standard atmospheric conditions. A time step is selected with regard to initial velocity and air resistance and adapted to the trajectory. The program is considered to be cost effective when many trajectories are to be calculated...
Keywords: DAYTIME; LENGTH; REDUCTION; PERIODIC VARIATIONS; SPACE PROBES
Downloads: 234
[texts]MECA Symposium on Mars: Evolution of its Climate and Atmosphere - NON
The geological, atmospheric, and climatic history of Mars is explored in reviews and reports of recent observational and interpretive investigations. Topics addressed include evidence for a warm wet climate on early Mars, volatiles on Earth and on Mars, CO2 adsorption on palagonite and its implications for Martian regolith partitioning, and the effect of spatial resolution on interpretations of Martian subsurface volatiles...
Keywords: BACKSCATTERING; ICE; SURFACE ROUGHNESS; GAUSS EQUATION; PERIODIC VARIATIONS; SPATIAL DISTRIBUTION
Downloads: 116
[texts]The Aggregate Description of Semi-Arid Vegetation with Precipitation-Generated Soil Moisture Heterogeneity - White, Cary B.
Meteorological measurements in the Walnut Gulch catchment in Arizona were used to synthesize a distributed, hourly-average time series of data across a 26.9 by 12.5 km area with a grid resolution of 480 m for a continuous 18-month period which included two seasons of monsoonal rainfall. Coupled surface-atmosphere model runs established the acceptability (for modelling purposes) of assuming uniformity in all meteorological variables other than rainfall...
Keywords: ASTROPHYSICS; SURVEYS; PERIODIC VARIATIONS; UNIVERSITIES; INDUSTRIES; LABORATORIES; PRIORITIES
Downloads: 53
[texts]Short and long term variations in the solar constant - Schatten, K. H
Short and long term variations in the solar constant are examined theoretically. The variations observed by the Solar Maximum Mission, lasting several days and associated with the passage of sunspot groups, strikingly demonstrates the well known lack of a bright ring effect around sunspots. This suggests that sunspot magnetic fields do not simply block the heat flowing upward into the photosphere. Rather, it is suggested that gravitational draining occurs; this cools sunspots and transports down...
Keywords: PERIODIC VARIATIONS; SOLAR CONSTANT; VARIABILITY; CALIBRATING; NIMBUS 7 SATELLITE; PYROHELIOMETERS
Downloads: 71
[texts]Magnetic bremmstrahlung in a variable field as the mechanism behind the changing radiance of quasistellar radio sources (magnitotormoznoye izlucheniye v peremennom pole kak mekhanizm menyayushcheysya svetimosti kvazizvezdnykh radioistochnikov) - Ozernoy, L. M
Magnetic bremmsstrahlung in variable field as mechanism for changing radiance of quasi-stellar radio sources
Keywords: BREMSSTRAHLUNG; MAGNETIC FIELDS; PERIODIC VARIATIONS; QUASARS; RADIANCE; BREMSSTRAHLUNG; QUASI-STELLAR RADIO SOURCE /QSO/
Downloads: 47
[texts]Theoretical investigation of the radiant emission spectrum from the fuel region of a nuclear light bulb engine - Krascella, N. L
Spectral emission characteristics of fuel region of nuclear light bulb engine
Keywords: DEGREES OF FREEDOM; NONLINEAR SYSTEMS; OSCILLATORS; SYSTEMS ANALYSIS; AMPLITUDES; ELECTRON OSCILLATIONS; PERIODIC VARIATIONS; PHASE SHIFT CIRCUITS
Downloads: 68
[texts]Flight of Soyuz 10 - NON
Soyuz 10 launch and docking with Salyut space station
Keywords: CYCLONES; PERIODIC VARIATIONS; PROBABILITY THEORY; STATISTICAL ANALYSIS; TROPICAL STORMS; WEATHER STATIONS; ATLANTIC OCEAN; CLIMATOLOGY; METEOROLOGICAL SERVICES
Downloads: 96
[texts]Low-Complexity, Digital Encoder/Modulator Developed for High-Data-Rate Satellite B-ISDN Applications - NON
The Space Electronics Division at the NASA Lewis Research Center is developing advanced electronic technologies for the space communications and remote sensing systems of tomorrow. As part of the continuing effort to advance the state-of-the-art in satellite communications and remote sensing systems, Lewis developed a low-cost, modular, programmable, and reconfigurable all-digital encoder-modulator (DEM) for medium- to high-data-rate radiofrequency communication links...
Keywords: X RAY ASTRONOMY; RADIO GALAXIES; LIGHT CURVE; PERIODIC VARIATIONS; X RAY TIMING EXPLORER
Downloads: 78
[texts]Particle flow within a transonic compressor rotor passage with application to laser-Doppler velocimetry - Maxwell, B. R
A theoretical analysis was conducted of the dynamic behavior of micron size particles moving in the three-dimensional flow field of a rotating transonic axial-flow air compressor rotor. The particle velocity lag and angular deviation relative to the gas were determined as functions of particle diameter, mass density and radial position. Particle size and density were varied over ranges selected to correspond to typical laser-Doppler velocimeter (LDV) flow field mapping applications...
Keywords: ASTRONOMICAL PHOTOGRAPHY; CARBON DIOXIDE; PLANETARY ATMOSPHERES; VENUS (PLANET); PERIODIC VARIATIONS; SPECTRUM ANALYSIS; TEMPERATURE EFFECTS
Downloads: 81
[texts]THREE-DIMENSIONAL LUNAR TRAJECTORIES - EGOROV, V. A
THREE DIMENSIONAL LUNAR TRAJECTORY ANALYSES TO FIND ENERGETICALLY OPTIMUM TRAJECTORIES
Keywords: ABSORPTION SPECTRA; JUPITER (PLANET); ULTRAVIOLET SPECTRA; ENERGY DISTRIBUTION; MONOCHROMATIC RADIATION; PERIODIC VARIATIONS; SOLAR ACTIVITY; SPECTROGRAMS
Downloads: 112
[texts]An Overview of NASA's In-Space Cryogenic Propellant Management Technologies - Tucker, Stephen
Future mission planning within NASA continues to include cryogenic propellants for in space transportation, with mission durations ranging from days to years. Between 1995 and the present, NASA has pursued a diversified program of ground-based testing to prepare the various technologies associated with in-space cryogenic fluid management (CFM) for implementation. CFM technology areas being addressed include passive insulation, zero gravity pressure control, zero gravity mass gauging, capillary l...
Keywords: ANGULAR MOMENTUM; DATA SYSTEMS; KINETIC ENERGY; TORQUE; ATMOSPHERIC MODELS; AIR MASSES; TRENDS; PERIODIC VARIATIONS; MOUNTAINS
Downloads: 144
[texts]NASA Glen Steady-State Heat Pipe Code Users Manual, DOS Input - Tower, Leonard K
The heat pipe code LERCHP has been revised, corrected, and extended. New features include provisions for pipes with curvature and bends in ''G'' fields. Heat pipe limits are examined in detail and limit envelopes are shown for some sodium and lithium-filled heat pipes. Refluxing heat pipes and gas-loaded or variable conductance heat pipes were not considered.
Keywords: EL NINO; PERIODIC VARIATIONS; SOUTHERN OSCILLATION; AIR WATER INTERACTIONS; CLIMATE CHANGE; SEA SURFACE TEMPERATURE
Downloads: 124
[texts]X-38 V201 Avionics Architecture - Bedos, Thierry
The X-38 is an experimental NASA project developing a core human capable spacecraft at a fraction of the cost of any previous human rated vehicle. The first operational derivative developed from the X-38 program will be the International Space Station (ISS) Crew Return Vehicle (CRV). Although the current X-38 vehicles are designed as re-entry vehicles only, the option exists to modify the vehicle for uses as an upward vehicle launched from an expendable launch vehicle or from the X-33 operationa...
Keywords: FOLDING; TRAJECTORIES; WATER; MOLECULAR DYNAMICS; PEPTIDES; RESEARCH; SIMULATION; ADSORPTION; FREE ENERGY; PERIODIC VARIATIONS; STRANDS
Downloads: 134
[texts]Particle detection apparatus Patent - Kinard, W. H
Particle detector for indicating incidence and energy of minute space particles
Keywords: CHANNEL FLOW; GAS FLOW; OSCILLATING FLOW; PERIODIC VARIATIONS; SPATIAL DISTRIBUTION; LATTICE PARAMETERS; PLATES; SUBSONIC FLOW
Downloads: 76
[texts]Energy absorbing structure Patent Application - Keathley, W. H.
Low onset rate energy absorber in form of strut assembly for crew couch of Apollo command module
Keywords: LEAVES; LEGUMINOUS PLANTS; PERIODIC VARIATIONS; AGRICULTURE; DARKNESS; DIURNAL VARIATIONS; LIGHT (VISIBLE RADIATION); MOTION
Downloads: 47
[texts]Ionizing radiations and parameters modifying radiation sterilization - NON
No Abstract Available
Keywords: COMPUTATION; EQUATIONS OF MOTION; PERTURBATION; FOURIER SERIES; FOURIER TRANSFORMATION; JACOBI INTEGRAL; MATHEMATICAL MODELS; PERIODIC VARIATIONS
Downloads: 70
[texts]Machine Dynamics Branch Research and Accomplishments for FY 1996 - Stefko, George L
This publication contains a collection of fiscal year 1996 research highlights from the Machine Dynamics Branch at NASA Lewis Research Center. Highlights from the branch's major work areas - Turbomachinery Aeroelasticity, Vibration Control and Magnetic Suspension Systems, Dynamic Systems Response and Analysis, and Computational Structural Methods - are included in the report as well as a listing of the fiscal year 1996 branch publications.
Keywords: ASTROPHYSICS; CATACLYSMIC VARIABLES; PERIODIC VARIATIONS; PHOTOMETRY; COMPUTERS; COSTS; EPHEMERIDES; SENSITIVITY; TELESCOPES
Downloads: 57
[texts]The Nature and Evolutionary History of GRO J1744-28 - Rappaport, S
GRO J1744-28 is the first known X-ray source to display bursts, periodic pulsations, and quasi-periodic oscillations. This source may thus provide crucial clues that will lead to an understanding of the differences in the nature of the X-ray variability from various accreting neutron stars. The orbital period is 11.8 days, and the measured mass function of 1.31 x 10(exp -4) solar mass is one of the smallest among all known binaries...
Keywords: ARCTIC OCEAN; TRENDS; ANTARCTIC REGIONS; ARCTIC REGIONS; OSCILLATIONS; PERIODIC VARIATIONS; TIME SERIES ANALYSIS; SEA ICE; AMPLITUDE MODULATION; DECOMPOSITION
Downloads: 64
[texts]Intra-seasonal Oscillations (ISO) of Zonal-Mean Meridional Winds and Temperatures as Measured by UARS - Huang, Frank T.
Based on an empirical analysis of measurements with the High Resolution Doppler Imager (HRDI) on the UARS spacecraft in the upper mesosphere (95 km), persistent and regular intra-seasonal oscillations (ISO) with periods of about 2 to 4 months have recently been reported in the zonal-mean meridional winds. Similar oscillations have also been discussed independently in a modeling study, and they were attributed to wave-mean-flow interactions...
Keywords: SOLAR CYCLES; SOLAR CORPUSCULAR RADIATION; ENERGETIC PARTICLES; PERIODIC VARIATIONS; CORONAL MASS EJECTION; SOLAR STORMS; SOLAR RADIO BURSTS
Downloads: 51
[texts]Resolving the Large Scale Spectral Variability of the Luminous Seyfert 1 Galaxy 1H 0419-577: Evidence for a New Emission Component and Absorption by Cold Dense Matter - Pounds, K. A.
An XMM-Newton observation of the luminous Seyfert 1 galaxy 1H 0419-577 in September 2002, when the source was in an extreme low-flux state, found a very hard X-ray spectrum at 1-10 keV with a strong soft excess below -1 keV. Comparison with an earlier XMM-Newton observation when 1H 0419-577 was X-ray bright indicated the dominant spectral variability was due to a steep power law or cool Comptonised thermal emission...
Keywords: CLIMATE CHANGE; MASS DISTRIBUTION; GLACIERS; GEOPHYSICS; SATELLITE LASER RANGING; VARIABILITY; EARTH GRAVITATION; EL NINO; MASS TRANSFER; PERIODIC VARIATIONS; SOUTHERN OSCILLATION
Downloads: 73
[texts]The Galley Parallel File System - Nieuwejaar, Nils
As the I/O needs of parallel scientific applications increase, file systems for multiprocessors are being designed to provide applications with parallel access to multiple disks. Many parallel file systems present applications with a conventional Unix-like interface that allows the application to access multiple disks transparently. The interface conceals the parallelism within the file system, which increases the ease of programmability, but makes it difficult or impossible for sophisticated pr...
Keywords: GEOMAGNETISM; MAGNETIC DISTURBANCES; SOLAR WIND; PERIODIC VARIATIONS; SOLAR PLANETARY INTERACTIONS; FAST FOURIER TRANSFORMATIONS; EXPLORER 50 SATELLITE; SOLAR WIND VELOCITY
Downloads: 63
[texts]X-33 Metallic TPS Tests in NASA-LaRC High Temperature Tunnel - Bouslog, Stanley A.
Conclusions The first series of metallic TPS tests in the NASA-LaRC Mach 7 High Temperature Tunnel has been completed. Additional testing is 'in progress and shall provide data for off-design configurations for the metallic TPS. The available data are being analyzed and being used to correlate analytical models to be used for X-33 flight design analysis. The final paper shan present additional data from these tests and comparisons between the data and analytical predictions.
Keywords: AIR WATER INTERACTIONS; MEASURING INSTRUMENTS; TIME SERIES ANALYSIS; PERIODIC VARIATIONS; OCEAN MODELS; HEAT FLUX; OSCILLATIONS; VARIABILITY; STORMS; SPECTRUM ANALYSIS
Downloads: 69
[texts]Silicon Effects on Properties of Melt Infiltrated SiC/SiC Composites - Bhatt, Ramakrishna T.
Silicon effects on tensile and creep properties, and thermal conductivity of Hi-Nicalon SiC/SiC composites have been investigated. The composites consist of 8 layers of 5HS 2-D woven preforms of BN/SiC coated Hi-Nicalon fiber mats and a silicon matrix, or a mixture of silicon matrix and SiC particles. The Hi-Nicalon SiC/silicon and Hi-Nicalon SiC/SiC composites contained about 24 and 13 vol silicon, respectively...
Keywords: EL NINO; PERIODIC VARIATIONS; SEA SURFACE TEMPERATURE; SOUTHERN OSCILLATION; CLIMATOLOGY; AIR WATER INTERACTIONS; TROPICAL METEOROLOGY; CLIMATE CHANGE
Downloads: 84
[texts]Preliminary analysis of accelerated space flight ionizing radiation testing - Wilson, J. W.
A preliminary analysis shows that radiation dose equivalent to 30 years in the geosynchronous environment can be accumulated in a typical composite material exposed to space for 2 years or less onboard a spacecraft orbiting from perigee of 300 km out to the peak of the inner electron belt (approximately 2750 km). Future work to determine spacecraft orbits better tailored to materials accelerated testing is indicated...
Keywords: CLIMATE; LUNAR TIDES; PERIODIC VARIATIONS; SUNSPOTS; CYCLES; DROUGHT; PREDICTION ANALYSIS TECHNIQUES; SOLAR MAGNETIC FIELD; SUNSPOT CYCLE; TIDES; CLIMATOLOGY; FORECASTING
Downloads: 87
[texts]Integrated Advanced Microwave Sounding Unit-A (AMSU-A). Engineering Test Report: AMSU-A1 METSAT Instrument (S/N 105) Qualification, Level Vibration Tests of December 1998 (S/O 605445, OC-419) - Heffner, R. J
This is the Engineering Test Report, AMSU-AL METSAT Instrument (S/N 105) Qualification Level Vibration Tests of December 1998 (S/0 605445, OC-419), for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A).
Keywords: CHINA; RIVERS; TROPICAL REGIONS; INDIAN OCEAN; PACIFIC OCEAN; SEA SURFACE TEMPERATURE; SUMMER; RAIN; PERIODIC VARIATIONS; VARIABILITY; EL NINO; DROUGHT; FLOODS
Downloads: 68
[texts]A Draft Test Protocol for Detecting Possible Biohazards in Martian Samples Returned to Earth - Rummel, John D.
This document presents the first complete draft of a protocol for detecting possible biohazards in Mars samples returned to Earth; it is the final product of the Mars Sample Handling Protocol Workshop Series, convened in 2000-2001 by NASA's Planetary Protection Officer. The goal of the five-workshop Series vas to develop a comprehensive protocol by which returned martian sample materials could be assessed for the presence of any biological hazard(s) while safeguarding the purity of the samples f...
Keywords: SUNSPOTS; SPECTRORADIOMETERS; FACULAE; SOLAR CYCLES; LIGHT (VISIBLE RADIATION); PERIODIC VARIATIONS; SOLAR RADIATION; DATA REDUCTION; ASTRONOMICAL MODELS; REGRESSION ANALYSIS
Downloads: 108
[texts]Monitoring solar-type stars - Lockwood, G. W
Old UBV and recent uvby photometry of solar-type dwarfs and other standard stars yield an upper limit of variability (determined by observational errors) of about 0.004 mag rms. A factor two improvement in this upper limit is achievable.
Keywords: PERIODIC VARIATIONS; SOLAR CONSTANT; STELLAR LUMINOSITY; CLIMATE; SATELLITE-BORNE INSTRUMENTS; SOLAR DIAMETER; SOLAR MAXIMUM MISSION; TEMPERATURE MEASUREMENT
Downloads: 51
[texts]Space Station Freedom Overview - Kohrs, Richard H
This document explains which countries and agencies participate in the development of Space Station Freedom, what the different structures on the station will be, and who is responsible for constructing them. The systems which will be operational in the baseline configuration of the station are listed, as is its assembly schedule. An overview of plans for space station evolution is also given.
Keywords: BIOGEOCHEMISTRY; COASTS; MODIS (RADIOMETRY); SPACE OBSERVATIONS (FROM EARTH); BIOSPHERE; PERIODIC VARIATIONS; ECOSYSTEMS; LIFE SCIENCES; OCEANS; SOIL MOISTURE; CLIMATE; FRESH WATER
Downloads: 72
[texts]Evolutionary variations of solar luminosity - Endal, A. S
Theoretical arguments for a 30% increase in the solar luminosity over the past 4.7 billion years are reviewed. A scaling argument shows that this increase can be predicted without detailed numerical calculations. The magnitude of the increase is independent of nuclear reaction rates, as long as conversion of hydrogen to helium provides the basic energy source of the Sun. The effect of the solar luminosity increase on the terrestrial climate is briefly considered...
Keywords: PERIODIC VARIATIONS; SOLAR CONSTANT; SOLAR SPECTRA; SPECTRAL ENERGY DISTRIBUTION; CLIMATE; LONG TERM EFFECTS; RADIOMETERS; SOLAR OSCILLATIONS; SUNSPOTS
Downloads: 109
[texts]Decision-Theoretic Control of Planetary Rovers - Zilberstein, Shlomo
Planetary rovers are small unmanned vehicles equipped with cameras and a variety of sensors used for scientific experiments. They must operate under tight constraints over such resources as operation time, power, storage capacity, and communication bandwidth. Moreover, the limited computational resources of the rover limit the complexity of on-line planning and scheduling. We describe two decision-theoretic approaches to maximize the productivity of planetary rovers: one based on adaptive planni...
Keywords: FORMATION FLYING; VECTORS (MATHEMATICS); TRAJECTORY OPTIMIZATION; SPACECRAFT TRAJECTORIES; TRANSFER ORBITS; VECTOR ANALYSIS; ALGORITHMS; PERIODIC VARIATIONS; BOUNDARY CONDITIONS
Downloads: 139
[texts]Debris/Ice/TPS Assessment and Integrated Photographic Analysis of Shuttle Mission STS-82 - Katnik, Gregory N.
A debris/ice/thermal protection system assessment and integrated photographic analysis was conducted for Shuttle mission STS-82. Debris inspections of the flight elements and launch pad were performed before and after launch. Icing conditions on the External Tank were assessed by the use of computer programs and infrared scanned data during cryogenic loading of the vehicle, followed by on-pad visual inspection...
Keywords: FOURIER TRANSFORMATION; TRIGONOMETRIC FUNCTIONS; INTEGERS; DETECTION; APPLICATIONS PROGRAMS (COMPUTERS); HIGH RESOLUTION; DISCRETE FUNCTIONS; ALGORITHMS; COMPUTATION; INTERPOLATION; PERIODIC VARIATIONS; SEQUENCING
Downloads: 78
[texts]Electricity of the free atmosphere - Chubarina, E. V.
Electric field of free atmosphere
Keywords: ATMOSPHERIC ELECTRICITY; ELECTRIC FIELDS; FREE ATMOSPHERE; CHARGE DISTRIBUTION; CLOUDS (METEOROLOGY); ELECTRIC POTENTIAL; PERIODIC VARIATIONS; SOUNDING; SPACE CHARGE
Downloads: 270
[texts]Methods for presentation and display of multivariate data - Myers, R. H
Methods for the presentation and display of multivariate data are discussed with emphasis placed on the multivariate analysis of variance problems and the Hotelling T(2) solution in the two-sample case. The methods utilize the concepts of stepwise discrimination analysis and the computation of partial correlation coefficients.
Keywords: NORTHERN HEMISPHERE; METEOROLOGICAL PARAMETERS; STATISTICAL DISTRIBUTIONS; OZONE; PERIODIC VARIATIONS; PRESSURE DISTRIBUTION; SOUTHERN HEMISPHERE; STRATOSPHERE RADIATION; CLIMATOLOGY; DYNAMIC CHARACTERISTICS; MATHEMATICAL MODELS
Downloads: 121
[texts]Deterministic and Probabilistic Creep and Creep Rupture Enhancement to CARES/Creep: Multiaxial Creep Life Prediction of Ceramic Structures Using Continuum Damage Mechanics and the Finite Element Method - Jadaan, Osama M.
High temperature and long duration applications of monolithic ceramics can place their failure mode in the creep rupture regime. A previous model advanced by the authors described a methodology by which the creep rupture life of a loaded component can be predicted. That model was based on the life fraction damage accumulation rule in association with the modified Monkman-Grant creep ripture criterion However, that model did not take into account the deteriorating state of the material due to cre...
Keywords: LUNAR TIDES; ESTIMATING; SATELLITE TRACKING; ANGULAR MOMENTUM; DIURNAL VARIATIONS; OCEAN CURRENTS; PERIODIC VARIATIONS; TORQUE; EARTH ROTATION; ALTIMETERS; FREQUENCIES
Downloads: 91
[texts]A pulse-forming network for particle path visualization - Mcalister, K. W
A procedure is described for visualizing nonsteady fluid flow patterns over a wide velocity range using discrete nonluminous particles. The paramount element responsible for this capability is a pulse-forming network with variable inductance that is used to modulate the discharge of a fixed amount of electrical energy through a xenon flashtube. The selectable duration of the resultant light emission functions as a variable shutter so that particle path images of constant length can be recorded...
Keywords: ERROR ANALYSIS; STATISTICAL DISTRIBUTIONS; OZONE; PERIODIC VARIATIONS; STATISTICAL ANALYSIS; TIME SERIES ANALYSIS; TRENDS; DYNAMIC CHARACTERISTICS; FORECASTING; SATELLITE OBSERVATION
Downloads: 75
[texts]Preliminary Study of a Model Rotor in Descent - McAlister, K. W.
Within a program designed to develop experimental techniques for measuring the trajectory and structure of vortices trailing from the tips of rotor blades, the present preliminary study focuses on a method for quantifying the trajectory of the trailing vortex during descent flight conditions. This study also presents rotor loads and blade surface pressures for a range of tip-path plane angles and Mach numbers...
Keywords: ECOSYSTEMS; STATE VECTORS; RESILIENCE; REMOTE REGIONS; GROUND TRUTH; CLIMATE CHANGE; ANTHROPOLOGY; ARID LANDS; ECOLOGY; PERIODIC VARIATIONS; WEATHER; WATER RESOURCES; VARIABILITY
Downloads: 75
[texts]Derivation of Tropospheric Column Ozone from the EPTOMS/GOES Co-Located Data Sets using the Cloud Slicing Technique - Ahn, C.
A recently developed technique called cloud slicing used for deriving upper tropospheric ozone from the Nimbus 7 Total Ozone Mapping Spectrometer (TOMS) instrument combined together with temperature-humidity and infrared radiometer (THIR) is no longer applicable to the Earth Probe TOMS (EPTOMS) because EPTOMS does not have an instrument to measure cloud top temperatures. For continuing monitoring of tropospheric ozone between 200-500hPa and testing the feasibility of this technique across spacec...
Keywords: CORONAL MASS EJECTION; INTERPLANETARY MEDIUM; SOLAR WIND; SOLAR PROMINENCES; PERIODIC VARIATIONS; SOLAR ACTIVITY EFFECTS; SUN; SOLAR TERRESTRIAL INTERACTIONS
Downloads: 84
[texts]Cellular immune response: Experiment MA-031 - Criswell, B. S.
The cellular immune response of ASTP crewmembers was studied before and after the flight. Parameters studied were white blood cell concentrations, lymphocyte numbers, B- and T-lymphocyte responsiveness to PHA, pokeweed mitogen, Concanavalin A, and influenza virus antigen. Changes in the responsiveness of peripheral blood lymphocytes to phytohemagglutinin (PHA) occurred in the cellular immune response but no quantitative changes in lymphocytes were noted...
Keywords: APOLLO SOYUZ TEST PROJECT; EMISSION SPECTRA; X RAY SOURCES; PERIODIC VARIATIONS; PULSARS; SUPERNOVA REMNANTS; X RAY ASTRONOMY
Downloads: 90
[texts]Parallel NPARC: Implementation and Performance - Townsend, S. E
Version 3 of the NPARC Navier-Stokes code includes support for large-grain (block level) parallelism using explicit message passing between a heterogeneous collection of computers. This capability has the potential for significant performance gains, depending upon the block data distribution. The parallel implementation uses a master/worker arrangement of processes. The master process assigns blocks to workers, controls worker actions, and provides remote file access for the workers...
Keywords: GYRES; CONVERGENCE; LOW FREQUENCIES; OCEANS; SHEAR STRESS; ALASKA; CLIMATOLOGY; MARKOV PROCESSES; PERIODIC VARIATIONS; TOPOGRAPHY; WHITE NOISE; WAVE PROPAGATION; ANOMALIES
Downloads: 68
[texts]Real-Time Cloud, Radiation, and Aircraft Icing Parameters from GOES over the USA - Minnis, Patrick
A preliminary new, physically based method for realtime estimation of the probability of icing conditions has been demonstrated using merged GOES-10 and 12 data over the continental United States and southern Canada. The algorithm produces pixel-level cloud and radiation properties as well as an estimate of icing probability with an associated intensity rating Because icing depends on so many different variables, such as aircraft size or air speed, it is not possible to achieve 100% success with...
Keywords: PERIODIC VARIATIONS; CLOUD PHYSICS; RADIATION MEASUREMENT; CLOUDS (METEOROLOGY); RADIATION DISTRIBUTION; CLOUD COVER; OPTICAL THICKNESS; MODIS (RADIOMETRY); TRMM SATELLITE; RADIANCE
Downloads: 78
[texts]The relative importance of prebiotic synthesis on the Earth and input from comets and meteorites - Miller, S. L
The prebiotic synthesis of hydrogen cyanide and formaldehyde was studied by the action of electric discharges on various model primitive atmospheres containing CH4, CO, and CO2. Photochemical production rates would also have been important and were calculated for HCN and H2CO. A reasonable rate of synthesis of amino acids from these sources is about 10 n moles/(sq cm yr) or 0.10 moles/sq cm in 10(exp 7) yrs...
Keywords: ADAPTATION; BIOLOGICAL DIVERSITY; DEEP WATER; DOCUMENTS; HABITATS; PERIODIC VARIATIONS; TAXONOMY; BIOLOGICAL EVOLUTION; BIOLOGICAL MODELS (MATHEMATICS); DATA BASES; EXTINCTION; FOSSILS; MARINE BIOLOGY; PALEONTOLOGY; ANIMALS
Downloads: 27
[texts]Numerical methods and a computer program for subsonic and supersonic aerodynamic design and analysis of wings with attainable thrust considerations - Carlson, H. W.
This paper describes methodology and an associated computer program for the design of wing lifting surfaces with attainable thrust taken into consideration. The approach is based on the determination of an optimum combination of a series of candidate surfaces rather than the more commonly used candidate loadings. Special leading-edge surfaces are selected to provide distributed leading-edge thrust forces which compensate for any failure to achieve the full theoretical leading-edge thrust, and a ...
Keywords: BAYS (TOPOGRAPHIC FEATURES); INFRARED IMAGERY; INFRARED SCANNERS; TEMPERATURE MEASUREMENT; DATA ACQUISITION; MISSISSIPPI; OCEAN SURFACE; OCEANOGRAPHIC PARAMETERS; PERIODIC VARIATIONS; REMOTE SENSING; WATER TEMPERATURE; EARTH RESOURCES
Downloads: 108
[texts]Collisional Removal of OH (X (sup 2)Pi, nu=7) by O2, N2, CO2, and N2O - Knutsen, Karen
Collisional removal rate constants for the OH (X 2PI, nu = 7) radical are measured for the colliders O2, CO2, and N2O, and an upper limit is established for N2. OH(nu = 4) molecules, generated in a microwave discharge flow cell by the reaction of hydrogen atoms with ozone, are excited to v = 7 by the output of a pulsed infrared laser via direct vibrational overtone excitation. The temporal evolution of the P = 7 population is probed as a function of the collider gas partial pressure by a time-de...
Keywords: MESOSPHERE; PERIODIC VARIATIONS; NOCTURNAL VARIATIONS; NEUTRAL ATMOSPHERES; MERIDIONAL FLOW; FABRY-PEROT INTERFEROMETERS; INTERFEROMETERS; HYDROXYL EMISSION; THERMOSPHERE; WINTER; WINDS ALOFT; WIND (METEOROLOGY); UPPER ATMOSPHERE RESEARCH SATELLITE (UARS); TEMPERATE REGIONS
Downloads: 54
[texts]Cycle Trades for Nuclear Thermal Rocket Propulsion Systems - White, C.
Nuclear fission has been used as a reliable source for utility power in the United States for decades. Even in the 1940's, long before the United States had a viable space program, the theoretical benefits of nuclear power as applied to space travel were being explored. These benefits include long-life operation and high performance, particularly in the form of vehicle power density, enabling longer-lasting space missions...
Keywords: TIDES; SEA LEVEL; AMPLITUDES; BOUNDARY LAYERS; ATMOSPHERIC PRESSURE; ALTIMETERS; TOPEX; FLOW EQUATIONS; OCEANS; POSEIDON SATELLITE; DEVIATION; EQUILIBRIUM; PERIODIC VARIATIONS; ELEVATION; NUMERICAL ANALYSIS; MATHEMATICAL MODELS; KINEMATICS; STRUCTURAL BASINS
Downloads: 140
[texts]Estimating short-term solar variations by a simple envelope matching technique - Chan, K. L.
A simple matching technique is explained which allows the computation of the response of the solar surface to perturbations which occur at any depth within the convective envelope of the Sun. This technique was applied to a perturbation of the convective efficiency (alpha-mechanism), and of the non-gas component of the pressure (beta-mechanism) in different regions of the convection zone. The results indicate that either perturbation affects the solar luminosity...
Keywords: CONFERENCES; SOLAR LIMB; SOLAR MAXIMUM MISSION; SOLAR NEUTRINOS; STELLAR EVOLUTION; SUN; TEMPERATURE MEASUREMENT; PERIODIC VARIATIONS; SOLAR CONSTANT; STELLAR STRUCTURE; CHROMOSPHERE; LIMB DARKENING; NIMBUS 7 SATELLITE; PHOTOSPHERE; SOLAR DIAMETER
Downloads: 52
[texts]Characterizing Aeroelastic Systems Using Eigenanalysis, Explicitly Retaining The Aerodynamic Degrees of Freedom - Heeg, Jennifer
Discrete time aeroelastic models with explicitly retained aerodynamic modes have been generated employing a time marching vortex lattice aerodynamic model. This paper presents analytical results from eigenanalysis of these models. The potential of these models to calculate the behavior of modes that represent damped system motion (noncritical modes) in addition to the simple harmonic modes is explored...
Keywords: SURFACE PROPERTIES; COMPUTERIZED SIMULATION; HEAT FLUX; STANDARD DEVIATION; SEA SURFACE TEMPERATURE; SALINITY; MATHEMATICAL MODELS; ATLANTIC OCEAN; VARIABILITY; ANOMALIES; OCEAN SURFACE; PERIODIC VARIATIONS; SEA ICE
Downloads: 62
[texts]Aeronautics Learning Laboratory for Science, Technology, and Research (ALLSTAR) - Levy, Cesar
We finished the material development of Level 1, Level 2 and most of Level 3. We created three new galleries, one of streaming videos enabling the user to select his/her appropriate speed of Internet connectivity for better performance. The second gallery on NASA's X-series aircraft and the third is on F-series aircraft. We also completed the placement and activation of all thirteen kiosks. We added one more kiosk over the number suggested in the proposal at Baker Aviation High School - a Dade C...
Keywords: PHOTOSYNTHESIS; RADIATION ABSORPTION; ENERGY BUDGETS; HEAT FLUX; CLIMATE; DIURNAL VARIATIONS; CARBON DIOXIDE CONCENTRATION; ATMOSPHERIC CIRCULATION; PERIODIC VARIATIONS; ATMOSPHERIC COMPOSITION; ATMOSPHERIC GENERAL CIRCULATION MODELS; ACTIVITY (BIOLOGY)
Downloads: 92
[texts]Development of battery separator composites - Schmidt, G. F.
Improved inorganic-organic separators developed by NASA were commercially prepared. A single-ply asbestos substrate was developed, as well as alternative substrates based on cellulose and on polypropylene fibers. The single-ply asbestos was bound with butyl rubber and was functionally superior to the formerly used polyphenylene oxide saturated sheet. Commercially prepared separators exhibited better measured separator properties than the NASA standard...
Keywords: CLIMATOLOGY; MATHEMATICAL MODELS; PROBABILITY THEORY; STATISTICAL DISTRIBUTIONS; TIME SERIES ANALYSIS; CONFERENCES; ERROR ANALYSIS; ERROR FUNCTIONS; OZONOSPHERE; PERIODIC VARIATIONS; TRENDS; DYNAMIC CHARACTERISTICS; FORECASTING
Downloads: 106
[texts]Electrolysis Propulsion for Spacecraft Applications - deGroot, Wim A.
Electrolysis propulsion has been recognized over the last several decades as a viable option to meet many satellite and spacecraft propulsion requirements. This technology, however, was never used for in-space missions. In the same time frame, water based fuel cells have flown in a number of missions. These systems have many components similar to electrolysis propulsion systems. Recent advances in component technology include: lightweight tankage, water vapor feed electrolysis, fuel cell technol...
Keywords: UNSTEADY FLOW; BLUFF BODIES; PERIODIC VARIATIONS; ANGLE OF ATTACK; SUBSONIC WIND TUNNELS; RECTANGULAR WINGS; FLOW DISTRIBUTION; SEPARATED FLOW; FREQUENCIES; AERODYNAMIC STALLING; PRESSURE OSCILLATIONS
Downloads: 233
[texts]1998 Research Reports: NASA/ASEE Summer Faculty Fellowship Program - NON
This document is a collection of technical reports on research conducted by the participants in the 1998 NASA/ASEE Summer Faculty Fellowship Program at the Kennedy Space Center (KSC). This was the 14th year that a NASA/ASEE program has been conducted at KSC. The 1998 program was administered by the University of Central Florida in cooperation with KSC. The program was operated under the auspices of the American Society for Engineering Education (ASEE) with sponsorship and funding from the Educat...
Keywords: X RAY TIMING EXPLORER; STELLAR MASS; X RAY BINARIES; BLACK HOLES (ASTRONOMY); X RAY ASTRONOMY; STELLAR SPECTRA; ACCRETION DISKS; SATELLITE OBSERVATION; DATA PROCESSING; PERIODIC VARIATIONS; MASS TRANSFER
Downloads: 126
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